The compound (3-trifluoromethyl-phenyl)acetonitrile is an important intermediate to agricultural and pharmaceutical chemicals and may be made directly from 3-trifluoromethyl benzyl chloride by treatment with sodium cyanide. For example, (3-trifluoromethylphenyl)acetonitrile is an intermediate for preparing herbicides disclosed in U.S. Pat. No. 4,568,376. However, to make large amounts of (3-trifluoromethyl-phenyl)acetonitrile in an economically advantageous manner, it is necessary to design a synthesis of 3-trifluoromethyl benzyl chloride which is economically feasible both in chemistry (e.g., selectivity and yields of the synthetic steps), use of reagents, and also in the apparatus utilized to conduct the processes.
It is thus an object of the present invention to provide a new process for preparing 3-trifluoromethyl benzyl chloride and (3-trifluoromethylphenyl)acetonitrile.
It is a further object of the present invention to provide an improved method for selectively monochlorinating 3-(chloromethyl) benzalchloride (sometimes referred to herein as CMBC or .alpha.,.alpha.,.alpha.'-trichloro-m-xylene) to form 3-(chloromethyl) benzotrichloride (sometimes referred to herein as CMBTC), the latter of which is a key intermediate to forming trifluoromethyl benzyl chloride.
These and other objects of the present invention will be apparent from the following description, the appended drawing and appended claims, and from practice of the invention.